Portable tank construction



Oct. 23, 1962 w. D. MITCHELL PORTABLE TANK CONSTRUCTION Filed Oct. 30, 1959 ffl m M 2 a .3 L m 3,059,802 Patented Oct. 23, 1952 tire 3,059,302 PORTABLE TANK CONSTRUCTION Wiley D. Mitchell, 672 S. Gerhart Ave., Los Angeles, Calif. Filed Oct. 30, 1959, Ser. No. 849,922 4 Claims. (Cl. 220-1) My present invention relates to portable tanks adapted to be carried by means of a handle or strapped on the back of a person, for carrying water or other liquids, or for use as sprayers for spraying liquid in fire extinguishing, insect control or the like; and it relates particularly to a novel plastic tank construction of this general character which is much less expensive to produce than the conventional metal tank, and which is superior to the conventional metal tank in a number of different ways.

Portable metal tanks are currently extensively used for carrying water and other liquids in areas where running water is not readily available. For example, tanks of this type are provided for fire control, having a carrying handle and alternative means for strapping these tanks to the back of a person, and being provided with a selectively engageable pumping device so that water or other liquid can be sprayed when desired. However, these metal tanks are difiicult and expensive to produce, requiring a number of welding and forming operations. Further, these conventional metal tanks tend to corrode internally, the corrosion scaling off into the liquid in the tank and clogging up the filtering screen and the spraying pump. Such clogging could be disastrous in fire control use of such a tank in the mountains or other remote areas.

Also, these metal tanks must be handled with con siderable care in order to prevent them from becoming dented or otherwise damaged in shipping and in operation.

A further problem in connection with conventional tanks of this general character is that projections formed thereon, such as an upwardly projecting handle and an upwardly projecting cap make them difiicult to stack for shipping and storage.

Also, these conventional tanks must embody a bafile plate across the inside in order to prevent the liquid from sloshing back and forth too much when the tank is being carried.

In view of these and other problems in connection with conventional metal tanks of this character, it is an object of my present invention to provide a portable plastic tank of the character described which is relatively simple and inexpensive to produce, being manufactured by a simple molding process.

Another object of my present invention is to provide a novel plastic tank of the character described which is rust and corrosion proof, and which is composed of a sufficiently pliable material to resist any permanent damage from blows received in handling or shipping.

Another object of my present invention is to provide a novel plastic tank of the character described in which the handle and cap members are positioned below the outer upper rim of the tank to permit stacking of a number of these tanks.

A further object of my present invention is to provide a novel tank construction of the character described in which the internal liquid-carrying chamber is divided into two generally cylindrical portions that are joined together at the center of the tank, whereby sloshing of liquid contained in the tank is held to a minimum by circular currents which tend to be established in the two generally cylindrically shaped portions, these separate circular currents tending to dampen each other.

A still further object of my present invention is to provide a plastic tank of the character described which, because of its pliability, is more comfortable than conventional tanks when carried on the back of a person, and also reduces back injuries which result from contact of the conventional heavy, rigid metal containers with the back.

Other objects and advantages of my present invention will be apparent from the following description and claims, the novelty of my invention consisting in the features of construction, the combination of parts, the novel relations of the members, and the relative proportioning, disposition and operation thereof, all as is more completely described herein and as is more particularly pointed out in the appended claims.

In the accompanying drawings, forming a part of my present specification:

FIGURE 1 is a perspective View of my present invention.

FIGURE 2 is a vertical section along the line 22 in FIGURE 1.

FIGURE 3 is a horizontal section along the line 3-3 of FIGURE 2, particularly illustrating my novel internal tank shape which minimizes sloshing of liquid contained therein.

FIGURE 4 is a vertical section along the line 4-4 in FIGURE 3.

Referring to my drawings, my present invention comprises a tank 10 preferably composed of a somewhat pliable plastic material such as polyethylene or other suitable plastic. Tank 10 includes a dished-out top portion 12, a bottom portion 14, a forward wall 16 adapted to be disposed against the back of the person carrying the tank when it is supported on the back, a rear wall 18, and curved side walls 20 and 22 which join the forward wall 16 and rear wall 18 together.

My tank 10 is preferably molded in any conventional manner in two halves, a top half and a bottom half, these halves being joined together after molding at a central, horizontal seam 23. The sections may be joined by heating, or in any other conventional manner.

I provide a vertical, V-shaped groove 24 in the forward wall 16, the groove 24 being relatively narrow so that it does not substantially interfere with the contouring of wall 16 to fit the back of a person carrying tank 10, but being sufi'iciently wide to provide room for the carrying handle 34 as hereinafter particularly described.

A similar opposed V-shaped groove 26 is provided in the rear wall 13.

Referring to FIGURE 3 of the drawings, it will be seen that this external shape of my tank 10 provides a pair of generally cylindrical internal walls 28 and 30 that are joined by a central vertical slot 32. This internal configuration of my tank 19 completely eliminates the need for the conventional baffle plate employed in such tanks to divide the tankrinto two half-sections in order to reduce sloshing of the liquid in the tank as the tank is being carried. My configuration tends to set up circular movements of the liquid in the respective halves defined by the generally cylindrical walls 28 and 30, these circular movements tending to discharge liquid from each half into the other half, thereby causing the movement in each half to dampen the corresponding movement in the other half. The net effect of this construction is that a minimum of sloshing is permitted within my tank without requiring any separate baffle plate, and accordingly, without requiring any separate molding of a baffle plate and aflixing of same within my tank 10.

I prefer to have the V-shaped grooves offset somewhat transversely to improve this baffling action. Thus, as best shown in FIGURE 3, while the groove 24 is centrally located between the sides of the tank, the groove 26 is offset closer to the side wall Ztl than to the side wall .22.

My carrying handle 34 is integrally molded across the upper part of the V-shaped groove 24, the handle 34 thus being conveniently disposed within the confines of the over-all tank shape without adding any projections on tank 10 which would interfere with stacking of a number of the tanks during storage or shipping.

The top portion 12 of the tank is provided with a transverse slot 36 adjacent to forward wall 16', slot 36 being suitable for frictional engagement of a pump (not shown) therein. Such a pump is used when my tank 10 is employed as a sprayer.

Disposed in the concave top 12 is an upwardly projecting circular boss 38 which flares outwardly to receive a snap-on cap 40 having an inwardly flaring flange 42 that frictionally mates with the outwardly flaring periphery of boss 38.

I provide a flexible retainer strap 44 which is integral with the top 12 at one end, and with the cap 40 at its other end, whereby the cap 40 will at all times be attached to tank 10, whether in the closed or in the open position. My external retainer strap 44 is much more sanitary and practical than the conventional internal chain used in comparable metal tanks.

I provide a pair of spaced cars 46 and 48 forming external projections on the top member 12, and a similar pair of integral, spaced cars 50 and 52 on the forward wall 16 toward the bottom, front portion of tank 10. These ears 46, 48, 50 and 52 are adapted to receive pivoting metal eyes 54 to which carrying straps (not shown) may be attached by conventional means, for supporting tank 10 on a persons back.

I provide a depending flange 56 of about three quarters of an inch in depth around the bottom 14 of tank 10 to protect the bottom 14 against injury.

A portion of curved side wall 22 near the bottom of tank 10 is molded to extra thickness at 58. This reinforced portion 58 may be left intact if it is desired to merely employ the tank 10 as a liquid carrying tank, and not as a sprayer. However, if tank 10 is to be used as a sprayer, a hole 59 may be punched through the reinforced portion 58 to provide for the insertion of a portable pump (not shown) such as that which may be supported within the longitudinal slot 36. Such a pump may be either frictionally engaged in a hole punched in the reinforced portion 58, or this reinforced portion or a metal insert therein may be provided with threads to which the pump may be operatively engaged.

I provide a filter structure adjacent to the reinforced portion 58 for filtering of any liquid that is ejected from tank 10 through opening 59, either during use of tank 10 as a sprayer or when the liquid is poured out for any other desired purpose. For example, if it is desired, a spigot (not shown) may be fastened to the reinforced portion 58 and connected with opening 59.

My presently preferred filter construction comprises a pair of spaced, vertical screen support members 60 and 62 integrally molded to the inner wall of tank 10 adjacent to the reinforced portion 58. These support members 60 and 62 are provided with generally vertical,

opposed slots 64 and 66 which are open at their tops and are thereby adapted to receive a generally rectangular filter screen 68 therein. I presently prefer to provide the filter screen 68 with a vertical portion 70 which actually slideably engages in the slots 64 and 66, and with a horizontal top portion 72 which extends outwardly to a point adjacent to the actual inner wall of tank 10, whereby all fluid admitted to hole 59 in the reinforced portion 58 would be filtered by the screen 68.

I provide a suitable handle 74 integrally attached to the top of screen 68 to facilitate the insertion and removal of screen 68 from its operative position.

In addition to the foregoing structure, it is desirable also to provide an integral annular projection 76 on the top portion 12 of the tank for attachment of additional pump or spray mechanism (not shown). Use of this projection 76 would include providing an opening through top 12 inside of the annular projection 76.

It will be apparent that I have provided a portable tank construction which is far simpler and less expensive to manufacture than conventional metal tanks. My present invention can be readily molded in two half-sections, thus eliminating all of the forming and welding operations heretofore required in connection with metal tanks. It will be noted that all of the members of both the upper and the lower half-sections of my device are so designed that each of these sections may be molded as a unit, and readily removed from the mold.

There is no problem of corrosion or rust in connection with my present tank, and it can be handled roughly without any danger of denting or other permanent damage, due to its pliability. Also, the pliable nature of my tank permits it to be worn relatively comfortably on the back of a person without danger of back injury.

My present invention is ideal for use in merely carrying liquids, and can be readily converted for use as a fire eX- tinguisher or other sprayer to replace the present metal tanks that are extensively used for this purpose in mountainous and other remote regions.

It is to be understood that the form of my invention herein shown and described is my preferred embodiment and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of my invention, or the scope of my appended claims.

I claim:

1. A portable tank for containing liquid which comprises: a body member having a lower edge and an upper edge, said body member in horizontal section being of oblong configuration having rounded ends and having sides formed with opposed, vertically arranged, V-shaped indentations extending from the lower edge to the upper edge and spaced apart from each other so as to divide said body into a pair of generally cylindrical, vertically arranged tank portions disposed side-by-side and communicating with each other between said indentations; a bottom closure mounted at said lower edge of the body; and a top closure mounted at said upper edge of the body; whereby liquid in said body tending to slosh from one tank portion to the other tank portion will be diverted by said V-shaped indentations into currents tending to circulate in each of said tank portions.

2. A portable tank as defined in claim 1, wherein said V-shaped indentations are offset with respect to each other so that one of said indentations is closer to one of said rounded ends than the other indentation, and so that said other indentation is closer to the other rounded end than said one indentation.

3. A portable tank as defined in claim 1 which includes an outlet hole extending through said body member adjacent to said bottom closure, a pair of spaced, generally vertical support members extending inwardly from the inner surface of said body member, said support members extending upwardly from the inner surface of said bottom closure on opposite sides of said outlet hole and having opposed, generally vertical slots therein, said slots being spaced inwardly from said inner surface of the body member and opening out from the tops of said support members, and a porous filter member removably slidably engageable in said slots, said filter member having a substantially greater area than the area defined by said outlet hole.

4. A portable tank as defined in claim 3, wherein said filter member has a horizontally arranged porous portion at its top extending from said slots substantially to said inner surface of the body member.

References Cited in the file of this patent UNITED STATES PATENTS 1,299,369 Mauzey Apr. 1, 1919 6 Parks Sept. '2, 1919 Daviss May 14, 1929 Pritchard June 28, 1932 Smith June 6, 1933 Benson Mar. 8, 1949 Lyon Dec. 16, 1952 Austin Oct. 27, 1953 Clement Apr. 19, 1955 Moon Dec. 20, 1955 .Tepson July 28, 1959 Taylor Oct. 6, 1959 Arne Mar. 21, 1961 FOREIGN PATENTS Netherlands Feb. 15, 1937 France Feb. 2, 1959 

